The invention relates to a photovoltaic concentrator module with multifunction frame and also to a method for production thereof. Concentrator modules of this type are used in particular in the field of concentrating solar technology.
In photovoltaics, there have been approaches made already for many years to operate with concentrated solar radiation. The principle is simple: solar radiation is concentrated with mirrors and/or lenses and directed onto special concentrator solar cells. The required surface area of expensive cell material is hence reduced. A crucial breakthrough in concentrator technology is now imminent. This is the case not least because, with highly efficient concentrator PV solar cells on a III-V basis, efficiencies of the cells of over 37% have been achieved and hence efficiencies in the modules of significantly above 25% are possible. The application of III-V solar cells in concentrator systems has been investigated for a long time. Sunlight is hereby focused with the help of Fresnel lenses by a factor 300 to 1,000 on a tiny focal spot in which then a small solar cell of still merely 2 to 10 mm2 is situated. The object of this procedure is to replace the expensive semiconductor surface of the III-V stacked cells for a comparatively economical lens system and consequently to make the application of this successful space technology also profitable on the ground.
Such concentrating photovoltaic systems serve for current generation, in particular in photovoltaic power plants. A large number of modules are mounted for this purpose on a tracking unit, a so-called tracker, which orientates the concentrator modules constantly towards the sun. The modules on a tracker are connected to each other electrically. This technology which is still very new has the advantages in the case of large-area use in particular, by enabling a cost reduction in photovoltaic current generation due to a high efficiency potential, of being able to be scaled into the gigawatt range without a shortage of raw materials and of having a short energy amortisation time.
Because of the higher complexity of concentrating photovoltaic systems in comparison with conventional flat modules, the former are suitable in particular for use in the power plant field. A certain amount of maintenance is required because of the controlled tracking and possible soiling of the lens system.